The squeaky-voiced 34-year-old was rather excited as he waited backstage, telling another act: "I've performed magic my whole life, but you never really know if you're any good until you do something like this."
Ant and Dec soon sent him on out stage with just a moment's notice, stunning him like a deer in headlights.
"Is he here by accident?" wondered Amanda Holden.
Matt - who described his style of magic as "a little bit crazy, a little bit variety" - kicked off his performance by explaining: "I'm gonna give this a big build up in the hope that everyone claps really loudly, and all the ladies take off their bras and throw them in my face.
"Looking at you, Alesha [Dixon]!"
Spotting her unimpressed reaction, he smirked: "It was worth a try!"
He then fidgeted about, while speaking in Spanish and doing his best impression of X Factor voiceover man's 'Rachel Adedeji'.
"It's like if Lee Evans done magic," Ant observed.
Finally Matt got in to his trick proper, pouring himself a shot of tequila - before realising he hadn't added any salt.
He eventually made a seemingly endless stream of salt pour out of his hand, ending with a toast to the audience.
"What a brilliant way to present a magic trick," reviewed David Walliams. "I love when people push jokes as far as they can possibly go. It was very funny, very entertaining."
Simon Cowell added: "When you started with that voice, I thought, 'this is gonna be really annoying'.
"Actually, you are brilliant. I'm surprised you haven't had a break yet, you're really likeable and nuts."
But the judges weren't the only people left in stitches by Matt's act - and just as they began to vote, Ant and Dec emerged from the sidelines and hit the Golden Buzzer, guaranteeing him a place in the live shows.
"Honestly, we were laughing so much I thought I was gonna pee myself," Ant explained.
"Simon you said it, for some reason he hasn't been given the break, so we wanted to do it," Dec added.
Matt ran off the confetti-covered stage to thank the boys, promising them: "There's so much that I want to show the world."
Matt joins singer Sarah Ikumu, dance group Just Us and comedian Daliso Chaponda in the Golden Buzzer line-up.
Only David is yet to reveal which hopeful he has given a fast-track to the semi-finals.